Search Results (4,017)

Fenbendazole is an important anti-parasitic medicine widely used in the veterinary field and has recently been considered as a possible anti-cancer agent in humans by some researchers. Fenbendazole encounters challenges in its usage due to its limited aqueous solubility, which consequently impacts its therapeutic efficacy. In this work, an in vitro mechanistic investigation was conducted to evaluate the compatibility, amorphization behaviour and dissolution profile of fenbendazole dispersed in Soluplus^® using the solid dispersion approach via hot-melt extrusion. Three different fenbendazole/Soluplus^® ratios were formulated and characterised through systematic experimentation. Powder X-Ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDX) and Fourier Transform Infrared Spectroscopy (FTIR) were employed for thermal, physical, chemical and morphological analyses. The solubility of the drug formulation during a dissolution test was investigated using Ultraviolet–Visible (UV–Vis) spectrophotometric measurements. In vitro dissolution testing in acidic and neutral media was employed as a controlled environment to compare dissolution behaviour among different loadings. The extrudates demonstrated markedly enhanced apparent solubility compared to neat fenbendazole, with the 5% formulation showing the highest dissolution rate (approximately 85% after 48 h). This improvement can be attributed to better wetting properties and drug dispersion within the Soluplus^® matrix. This innovative strategy holds promise in surmounting fenbendazole’s solubility limitations, presenting a comprehensive solution to enhance its therapeutic effectiveness. Full article

TiO₂ nanoparticles were synthesized by a simple sol–gel route followed by high-temperature calcination at 800 °C, aiming to obtain an anatase-dominant reference photocatalyst with enhanced structural stability after severe thermal treatment. Raman spectroscopy and X-ray diffraction confirmed that anatase is the major crystalline phase, with only a minor rutile contribution after calcination at 800 °C. Nitrogen adsorption–desorption measurements revealed a narrow mesoporous contribution arising from interparticle voids and a relatively high specific surface area (108 m² g⁻¹) despite the severe thermal treatment, while electron microscopy showed nanometric primary particles assembled into compact agglomerates. Surface hydroxyl groups were identified by Fourier-transform infrared spectroscopy, consistent with sol–gel-derived TiO₂ systems. Diffuse reflectance UV–Vis spectroscopy combined with Kubelka–Munk and Tauc analysis yielded an optical band gap of 3.12 eV, typical of anatase TiO₂. Methylene blue (MB) was used as a probe molecule to evaluate photocatalytic activity under ultraviolet and visible light irradiation. Under UV illumination, degradation kinetics were governed by band-gap excitation and reactive oxygen species generation, whereas a slower but reproducible reference behavior under visible light was predominantly associated with surface-related effects and dye sensitization rather than intrinsic visible-light absorption. Overall, the results establish this anatase-dominant TiO₂ as a reliable high-temperature reference photocatalyst, retaining measurable activity after calcination at 800 °C and exhibiting UV-driven behavior as the dominant contribution. Full article

In this study, the effects of molecular structure parameters of polycarboxylate ether (PCE)-based grinding aids (GAs) on grinding efficiency, cement properties, and powder flowability were systematically investigated. Existing literature indicates that only limited attention has been given to a comprehensive evaluation of the combined influence of PCE molecular weight, main chain-to-side chain ratio, and side chain characteristics on the grinding process and powder behavior. Within this framework, seven different PCE-based GAs were synthesized by systematically varying the main chain length, side chain length, and side chain/main chain ratio. The structural characterization of the synthesized additives was carried out using Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). Subsequently, the grinding efficiency, particle size distribution (PSD), and powder flowability of cements produced at two different GA dosages were evaluated in detail. The results demonstrated that increasing the GA dosage generally enhanced grinding efficiency and led to a narrower particle size distribution. An increase in main chain length at a constant side chain length improved grinding performance, whereas PCEs with a medium main chain length exhibited superior powder flowability. In contrast, increasing the side chain length alone had a limited effect on grinding efficiency. Considering all structural parameters collectively, the PCE5 additive—characterized by medium main and side chain lengths and a low side chain/main chain ratio—exhibited the most balanced and overall highest performance. Full article

Intensive agriculture has intensified soil acidification in southern China, threatening crop productivity and ecosystem sustainability. Biochar can neutralize acidity, improve pH buffering, and enhance nutrient retention and microbial habitat in acidic soils. Accordingly, we produced biochars from pruned eucalyptus (ABC), camphora (ZBC), and guava (FBC) branches via pyrolysis at 500 °C. The three biochars were characterized by elemental analysis, Fourier Transform Infrared Spectroscopy (FTIR), and SEM (Scanning Electron Microscopy), and their effects on soil properties, enzyme activities, and bacterial communities were evaluated through a 56-day incubation experiment in an acidified, continuously cropped soil. Physicochemical characterization revealed that ZBC and FBC possessed more oxygen-containing functional groups and greater potential for pH buffering and nutrient release, whereas ABC exhibited higher aromaticity and structural stability. Biochar significantly increased soil pH by 0.62–1.42 units and improved nutrient availability and carbon pools (p < 0.05). Additionally, 4% ZBC increased urease and sucrase activities by 21.54% and 79.34%, respectively, while 2% FBC increased cellulase activity by 25.99%. High-throughput sequencing identified Acidobacteria and Proteobacteria as the dominant phyla; ZBC and FBC at 0.5% and 2% significantly increased Shannon and Chao1 indices. Redundancy analysis indicated that available potassium, pH, soil organic carbon, urease, sucrase, and cellulase were the primary drivers of bacterial community variation and positively associated with carbon-cycling phyla. These findings demonstrate that feedstock-specific biochar properties critically regulate soil biogeochemical processes, offering a sustainable strategy to remediate acidified soils and valorize agroforestry residues. Full article

Against the backdrop of intensifying global population aging, lower-limb exoskeleton robots serve as core devices for rehabilitation and power assistance. Their control accuracy and motion smoothness rely on precise dynamic models. However, parameter uncertainties caused by variations in human lower limbs, assembly errors, and wear pose a critical bottleneck for accurate modeling. Aiming to achieve high-precision dynamic modeling for a two-degree-of-freedom lower-limb exoskeleton, this paper proposes a parameter identification method named Tent-GA-GWO. A dynamic model incorporating joint friction and link inertia was constructed and linearized. An excitation trajectory based on Fourier series, conforming to human physiological constraints, was designed. To enhance algorithm performance, Tent chaotic mapping was employed to optimize population initialization, a nonlinear control parameter was used to balance search behavior, and genetic algorithm operators were integrated to increase population diversity. Simulation results show that, compared to the traditional GWO algorithm, Tent-GA-GWO improved convergence efficiency by 32.1% and reduced the fitness value by 0.26%, demonstrating superior identification accuracy over algorithms such as GA and LIL-GWO. Validation on a physical prototype indicated a close agreement between the computed torque based on the identified parameters and the actual output torque, confirming the method’s effectiveness and engineering feasibility. This work provides support for precise control of exoskeletons. Full article

Sodium polyacrylate (PAAS) hydrogel is a functional polymer known for its excellent water absorption, retention, and thermal stability; however, its thermal conductivity behavior in engineering applications remains insufficiently understood. In this paper, two experimental setups were designed and constructed to measure the specific heat capacity and thermal conductivity of PAAS hydrogel in liquid, powder, and fluid–structure coupled states. The results show that the thermal conductivity initially increases rapidly with increasing water content and then decreases, achieving a maximum enhancement of 66% compared with PAAS powder. In contrast, the specific heat capacity exhibits an exponential increase and asymptotically approaches that of water. These findings demonstrate the thermal properties of PAAS hydrogel can be effectively tuned by adjusting its water content. Based on a composite material parameter model, simple predictive relationships for both specific heat capacity and thermal conductivity were established as functions of water content. Numerical simulations using the Fourier heat conduction equation validate the proposed models, with thermal relaxation behaviors in good agreement with experimental observations. Therefore, this work not only quantifies the thermal conductivity performance of PAAS hydrogels but also provides practical predictive models for the thermal design of hydrogel-based materials with enhanced heat transfer efficiency in engineering applications. Full article

Gadolinium-doped hydroxyapatite nanoparticles (HapGd NPs) have emerged as promising multifunctional platforms for biomedical applications due to their unique combination of biocompatibility, structural tunability, and magnetic responsiveness. In this work, HapGd nanoparticles were synthesized using a microwave-assisted method and subsequently functionalized with curcumin and folic acid to enhance therapeutic efficiency and selective targeting. The synthesized nanostructures were characterized using various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and relaxometry. Structural analyses revealed successful incorporation of Gd³⁺ ions into the Hap lattice, resulting in reduced unit cell volume and slight lattice distortion, while preserving the apatite crystalline framework. Surface functionalization with curcumin and folic acid was confirmed through spectroscopic characterization, demonstrating effective molecular attachment. Nuclear Magnetic Resonance (NMR) relaxation measurements indicated that Gd doping endowed paramagnetic behavior suitable for contrast enhancement in magnetic resonance imaging (MRI). Relaxometry studies revealed a strong linear correlation between 1/T₁ and the Gd³⁺ concentration, especially in the functionalized samples, with performance comparable to the commercial contrast agent Omniscan™. The developed HapGd-based nanoplatform exhibits integrated diagnostic and therapeutic potential, providing a foundation for future research in biomedical applications. Full article

This study investigated the effect of chickpea flour (CF) on the staling behavior of gluten-free bread (GFB) by comparing a formulation containing 50% rice flour (RF) and 50% CF (CFB) with a control bread based on rice flour supplemented with whey protein (RFB). Bread samples were stored at room temperature for up to 7 days. Changes in color, reflectance, starch and protein structure, specific volume, crumb structure, texture, and staling kinetics were monitored. CFB exhibited a darker and more yellow crumb and crust, with lower reflectance intensity, and showed greater color stability during storage. Fourier-transform infrared (FTIR) spectroscopy revealed higher overall starch crystallinity and more stable relative crystallinity degree (RCD) values in CFB (58.74–59.05%) compared to RFB (46.19–40.52%) throughout storage, indicating early amylose-driven ordering and a more stable molecular organization of starch. Protein secondary structure analysis showed that CFB had a higher β-sheet content (35.05–37.49) than the RFB formulation (30.37–31.16), indicating stronger protein aggregation. In contrast, macroscopic quality parameters showed that CFB had lower specific volume (1.65 vs. 1.93) and porosity (17.17 vs. 21.01 cm³/g) than RFB, resulting in higher hardness (15.92 vs. 6.15 N) and accelerated staling kinetics (k_corr) (0.28 vs. 0.14 day⁻¹), indicating faster crumb firming despite the observed molecular-level stability. Overall, the results demonstrated that CF contributes to enhanced molecular organization of starch and increased nutritional value of GFB, while its technological performance at the macroscopic level remains formulation-dependent. These findings highlight the need for targeted formulation and process optimization to balance molecular stability with desirable textural properties in CFB. Full article

This study investigates the design of bio-hybrid sandwich composites by combining polyester/glass skins with cores reinforced by continuous Musa paradisiaca fibres. The aim is to quantify how fibre weight fraction and alkaline surface treatment control the Charpy impact performance of these systems. Sandwich laminates were manufactured with three fibre loadings in the core (20, 25 and 30 wt.%), using fibres in the as-received condition and after alkaline treatment in NaOH solution. Charpy impact specimens were machined from the laminates and tested according to ISO 179-1. Fibre morphology and fracture surfaces were examined by scanning electron microscopy, while Fourier-transform infrared spectroscopy was used to monitor changes in surface chemistry after alkaline treatment. The combined effect of fibre content and treatment on absorbed energy was assessed through a two-way analysis of variance. Increasing Musa paradisiaca fibre content up to 30 wt.% enhanced the impact energy of the sandwich composites, and alkaline treatment further improved performance by strengthening fibre–matrix adhesion and promoting fibre pull-out, crack deflection and bridging mechanisms. The best Charpy impact response was obtained for cores containing 30 wt.% NaOH-treated fibres, demonstrating that surface modification and optimised fibre loading are effective design parameters for toughening polyester/glass bio-hybrid sandwich composites. Full article

This study reports the synthesis and detailed characterization of pullulan-isononanoate (Pull-Iso), as well as the preparation and characterization of Pull-Iso films incorporating liposomes loaded with silibinin (SB) and smoke tree (Cotinus coggygria) extract (STExt), to explore the physicochemical and functional properties of pullulan-based biomaterials for potential biomedical applications. Pullulan was successfully esterified with isononanoic acid chloride, as confirmed by ¹H and ¹³C NMR (Nuclear Magnetic Resonance) and Fourier Transform Infrared (FTIR) spectroscopy. Modification significantly reduced the glass transition temperature (Tg), indicating enhanced chain mobility due to the introduction of bulky side chains. Prepared liposomes, embedding SB and extracted smoke tree compounds, exhibited particle sizes ~2000 nm with moderate polydispersity (~0.340) and zeta potential values around –20 mV, demonstrating lower colloidal stability over 60 days, thereby justifying their encapsulation within films. Optical microscopy revealed uniform liposome dispersion in Pull-Iso film with 0.5 g of liposomes, while higher liposome loading (0.75 g of liposomes) induced aggregation and microstructural irregularities. Mechanical analysis showed a reduction in tensile strength and strain at higher liposome content. The incorporation of liposomes encapsulating STExt and SB significantly enhanced the antioxidant activity of Pull-Iso-based films in a concentration-dependent manner, as demonstrated by DPPH and ABTS radical scavenging assays. These preliminary findings suggest that pullulan esterification and controlled liposome incorporation may enable the development of flexible, bioactive-loaded films, which could represent a promising platform for advanced wound dressing applications, warranting further investigation. Full article

While deep learning methods are increasingly applied in the field of DOA estimation, existing approaches generally feed the real and imaginary parts of the covariance matrix directly into neural networks without optimizing the input features, which prevents classical attention mechanisms from improving accuracy. This paper proposes a spatio-temporal fusion model named DACL-Net for DOA estimation. The spatial branch applies a two-dimensional Fourier transform (2D-FT) to the covariance matrix, causing angles to appear as peaks in the magnitude spectrum. This operation transforms the original covariance matrix into a dark image with bright spots, enabling the convolutional neural network (CNN) to focus on the bright-spot components via an attention module. Additionally, a spectrum attention mechanism (SAM) is introduced to enhance the extraction of temporal features in the time branch. The model learns simultaneously from two data branches and finally outputs DOA results through a linear layer. Simulation results demonstrate that DACL-Net outperforms existing algorithms in terms of accuracy, achieving an RMSE of 0.04° at an SNR of 0 dB. Full article

The extensive consumption of freshwater resources and the continuous discharge of pharmaceutical residues pose serious risks to aquatic ecosystems and public health. In this study, pristine ZnO, TiO₂, Zn@TiO₂, and Ti@ZnO nanocomposites were synthesized via a precipitation-assisted solid–liquid interference method and systematically evaluated for the photocatalytic degradation of the antibiotic levofloxacin under UV and visible light irradiation. The structural, optical, and surface properties of the synthesized materials were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), UV–visible diffuse reflectance spectroscopy (UV–DRS), and X-ray photoelectron spectroscopy (XPS). XRD analysis confirmed the crystalline nature of all samples, while SEM images revealed spherical and agglomerated morphologies. Photocatalytic experiments were conducted using a 50-ppm levofloxacin solution with a catalyst dosage of 1 g L⁻¹. Pristine ZnO exhibited limited visible-light activity (33.81%) but high UV-driven degradation (92.98%), whereas TiO₂ showed comparable degradation efficiencies under UV (78.6%) and visible light (78.9%). Notably, Zn@TiO₂ nanocomposites demonstrated superior photocatalytic performance, achieving over 90% and near 70% degradation under both UV and visible light, respectively, while Ti@ZnO composites exhibited less than 60% degradation. The enhanced activity of Zn@TiO₂ is attributed to improved interfacial charge transfer, suppressed electron–hole recombination, and extended light absorption. These findings highlight Zn@TiO₂ nanocomposites as promising photocatalysts for efficient treatment of pharmaceutical wastewater under dual-light irradiation. Full article

The increasing consumption of highly processed foods has resulted in a reduced intake of essential vitamins, minerals, and bioactive compounds, thereby intensifying interest in the development of functional food. This study aimed to enrich fruit mousses with bioactive compounds derived from elderberry extract using an encapsulation strategy. Three formulations were prepared: a control mousse, a mousse enriched via direct addition of the extract, and a mousse supplemented with a nanoemulsion. Comprehensive analyses, including SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared Spectroscopy), colorimetry, texture and rheological measurements, phenolic acid and flavonoid content, antioxidant and reducing activity, sensory evaluation, and microbiological assessment, confirmed the successful formation of submicron capsules (400–900 nm), effective incorporation of grape seed oil into the fruit mousse formulations, and minimal color alteration (ΔE* < 1). The enriched mousses exhibited slightly higher hardness (7.5%) and adhesiveness (5.4%) as well as enhanced antioxidant and reducing activity compared to the control. Rheological analyses indicated improved structural stability resulting from fortification. Sensory evaluation demonstrated good consumer acceptance, while microbiological analyses suggested a potential shelf-life extension due to inhibited microbial growth. Overall, encapsulation proved to be an effective approach for incorporating elderberry-derived bioactive substances into fruit mousses while preserving product quality. Full article

In this study, we report a reproducible in situ photochemical method for the simultaneous synthesis of metallic and hybrid metal/metal oxide nanoparticles (NPs) within a UV–curable polymer matrix. A series of epoxy diacrylate-based formulations (BEA) was prepared, consisting of Epoxy diacrylate, Di(Ethylene glycol)ethyl ether acrylate (DEGEEA), and Phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide (BAPO), which served as a Type I photoinitiator. These formulations were designed to enable the simultaneous photopolymerization and photoreduction of metal precursors at various Ag⁺/Co²⁺ ratios, resulting in nanocomposites containing in situ-formed Ag NPs, cobalt oxide NPs, and hybrid Ag–Co₃O₄ nanostructures. The photochemical, magnetic, and dielectric properties of the resulting nanocomposites were evaluated in comparison with those of the pure polymer using UV–Vis and Fourier Transform Infrared Spectroscopy (FT-IR), Photo-Differential Scanning Calorimetry (Photo-DSC), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Impedance Analysis, and Vibrating Sample Magnetometry (VSM). Photo-DSC studies revealed that the highest conversion values were obtained for the BEA-Ag₁Co₁, BEA-Co, and BEA-Ag₁Co₂ samples, demonstrating that the presence of Co₃O₄ NPs enhances polymerization efficiency because of cobalt species participating in redox-assisted radical generation under UV irradiation, increasing the number of initiating radicals and leading to faster curing and higher final conversion. On the other hand, the Ag NPs, due to the SPR band formation at around 400 nm, compete with photoinitiator absorbance and result in a gradual decrease in conversion values. Crystal structures of the NPs were confirmed by XRD analyses. The dielectric and magnetic characteristics of the nanocomposites suggest potential applicability in energy-storage systems, electromagnetic interference mitigation, radar-absorbing materials, and related multifunctional electronic applications. Full article

Titanium (Ti) and its alloys are widely used in biomedical applications due to their biocompatibility and corrosion resistance; however, surface modifications are required to enhance biological functionality. Surface functionalization using natural biomolecules has emerged as a promising strategy to improve early cell–surface interactions and biocompatibility of implant materials. In this study, Ti6Al4V alloy surfaces were biofunctionalized using Spirulina platensis (S. platensis) biomass and protein extract to evaluate morphological, chemical, and biological effects. The functionalization process involved activation with piranha solution, silanization with 3-aminopropyltriethoxysilane (APTES), and subsequent biomolecule immobilization. Surface characterization by scanning electron microscopy (SEM), inductively coupled plasma mass spectrometry (ICP-MS), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) confirmed the successful incorporation of microalgal components, including nitrogen-, phosphorus-, and oxygen-rich organic groups. Biomass-functionalized surfaces exhibited higher phosphorus and oxygen content, while protein-coated surfaces showed nitrogen-enrich chemical signatures, reflecting the distinct molecular compositions of the immobilized biomolecules. Cell adhesion assays demonstrated enhanced early cell attachment on biofunctionalized surfaces, particularly in samples functionalized with 5 g/L biomass for three hours, which showed significantly greater cell attachment than both the control and protein-treated samples. These findings highlight the complementary yet distinct roles of S. platensis biomass and protein extract in modulating surface chemistry and cell–material interactions, emphasizing the importance of tailoring biofunctionalization strategies to optimize early biological responses on titanium-based implants. Full article